NEW YORK, Oct 1 (Reuters) - Railcar stocks including Trinity Industries were falling while the Dow Jones Transportation Average was down 1.7 percent with all 20 of its components in the red.
Concern about the first diagnosis of Ebola in a patient in the United States was weighing on companies related to transportation, with airline shares also down.
Trinity was down 5.7 percent on volume of 6.2 million shares in late morning trading, already more than its 10-day moving average volume of about 3 million. Shares of American Railcar Industries were down 3.5 percent.
Some oil industry leaders criticized this week proposed U.S. measures to increase safety when hauling crude oil on train lines. Such measures will drive up costs and do little to improve safety, they say.
The Dow Jones Transportation Average, often seen as a proxy for economic growth, was on track for its biggest daily percentage decline since June.
Index snapshot at 11:34 EDT:
* S&P 500 down 13.99 points, or 0.71 percent.
* Nasdaq Comp down 43.73 points, or 0.97 percent.
* Dow industrials off 166.97 points, or 0.98 percent.
* Russell 2000 down 5.76 points, or 0.52 percent.
* S&P MidCap down 6.19 points, or 0.45 percent.
* S&P SmallCap down 2.79 points, or 0.44 percent. (Editing by Bernadette Baum and Nick Zieminski)